The starter circuit shown in the figure was found in an old European documentation. The circuit makes use of an SCR which is still common and the diac can be of any type.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...